I teach some very gifted students. I would like to start some of them on recording their compositions on a relatively simple DAW. I would appreciate any suggestions you might have, Cakewalk or other.
Jack, the Quiet Bear

What kind of students? Do they have a strong background in sheet music, do they mostly play guitar or do they want to make beats on the computer?

^^^^ More info behind this would be helpful. A DAW is a tiny piece of the puzzle... do they have a computer? what are they recording (will they need an interface)? what is the intent? Do they have instruments/microphones?

Any DAW without the above is moot. Plus, there are DAW apps for phones that can achieve a great deal. Being that young, cost and whether they will take to it are also considerations, so "free" would be optimal until you know both of the above with some level of certainty.

Sonar Home studio is a pretty basic DAW and pretty diverse.
I would agree with what Sander just touched on though, What kind of music are they doing ?
Because something like Ableton wouldn't be my first choice for aspiring Rock stars.
Nor would FL studio for Orchestra students.
 

GARAGE BAND

 
Ok maybe that's a little on the extreme side but hear me out. You don't have to teach kids how to use DAW software. Instead, what you really need to teach them is how to record audio. There is no better way to teach/learn the fundamentals of recording audio than by using actual basic recording hardware. Teach them to record on tape. Teach them to mix on a mixer. Teach them the basics of the audio signal path. Teach them to use outboard processing with a mixer and recorder. 

Do that with them first and learning to use a DAW will be a piece of cake for them.

As far as DAWs go for talented young peeps, Sonar Home Studio is a good starting point. More details would be helpful though in order to point you in the best possible direction.

Mein gott a four track mixer. I remember I had a 4 track mixer made by Amstrad. My first experience of audio stuff. It had this pitch control where you could record things slower and play it back at normal with the pitch shift.

I will add that I suggest Home Studio because, while it is not as powerful as Sonar Artist, pro or Platinum, that's an advantage for someone who is just starting out. It has a lot fewer features but everything that is needed to get started, so it is functional but not overwhelming, and from my experience with kids, that's the sort of thing they need otherwise they easily get put off, distracted and lose interest. Home Studio would keep them engaged for now.

Although I agree that Home Studio might be the best choice but $49 to a 12 year old is a fortune.  You might google/bing free daws and see which one might be best for your  students.  You will find a number of them available.  YMMV